From the government’s press release (see also attached statement of facts from the plea agreement)

ALEXANDRIA, Va. – Yonathan Melaku, 23, of Alexandria, Va., pleaded guilty today to damaging property and firearms violations involving five separate shootings at military installations in northern Virginia between October and November 2010 and attempting to injure veterans’ memorials at Arlington National Cemetery.

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Melaku pleaded guilty to a three-count information that included injuring property of the United States, use of a firearm during a crime of violence and attempted injury to veterans’ memorials on U.S. property. The defense and government jointly recommended in the plea agreement a sentence of 25 years in prison. He will be formally sentenced on April 27, 2012.

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According to the statement of facts filed with his plea agreement, Melaku admitted that he carried out a series of five shootings from Oct. 17, 2010, through Nov. 2, 2010, at the following locations: the National Museum of the Marine Corps (twice), the Pentagon, a Marine Corps recruiting sub-station in Chantilly, Va., and a U.S. Coast Guard recruiting office in Woodbridge, Va. Each shooting took place late at night or early in the morning and involved multiple 9mm rounds fired at each building. The cost for repairs at the facilities exceeded $100,000.

Melaku admitted today that during the second shooting at the National Museum of the Marine Corps, he set up a video camera within the interior of his vehicle to record the shooting incident. The video shows Melaku repeatedly firing a handgun out the passenger-side window, and he narrates the incident on the video and states, among other things: That’s my target. That’s the military building. It’s going to be attacked” and at the conclusion of multiple shots exclaiming “Allahu Akbar” repeatedly.

In his statement of facts, Melaku stated that he attempted to flee law enforcement after being spotted on the property of Ft. Myer in Arlington, Va., at approximately 1:30 a.m. on June 17, 2011. During the pursuit, he dropped a backpack that contained numerous spent 9mm shell casings; four bags containing ammonium nitrate, and a spiral notebook with numerous Arabic statements referencing the Taliban, al Qaeda, Osama bin Laden, “The Path to Jihad,” as well as a list of several other individuals associated with foreign terrorist organizations.

Melaku admitted that, at the time of his apprehension, he was attempting to enter the area of Arlington National Cemetery containing graves of deceased Iraq and Afghanistan war veterans, intending to desecrate and injure the grave markers by spray-painting the markers with Arabic statements and by leaving the ammonium nitrate he was carrying at the sites of the grave markers.

On June 17, 2011, during a search of his residence, FBI search teams found Melaku had stored within the bedroom closet of his residence a typed list titled “Timer” that included nine items that Melaku admitted are consistent with what would be required to construct the firing mechanism for an explosive device. Four of those items had been crossed through.